package com.simple;

public class romanToInt13 {
/*    int sum = 0;
    int preNum = getValue(s.charAt(0));
        for(int i = 1;i < s.length(); i ++) {
        int num = getValue(s.charAt(i));
        if(preNum < num) {
            sum -= preNum;
        } else {
            sum += preNum;
        }
        preNum = num;
    }
    sum += preNum;
        return sum;*/

    public static void main(String[] args) {
        String s = "";
        int sum = 0;
        int preNum = getValue(s.charAt(0));
        for(int i =1;i<s.length();i++){
            int num = getValue(s.charAt(i));
            if(preNum < num){
                sum -= preNum;
            }else {
                sum += preNum;
            }
            preNum = num;
        }
        sum += preNum;
        System.out.println(sum);
    }

    private static int getValue(char ch ){
        switch (ch){
            case 'I': return 1;
            case 'V': return 5;
            case 'X': return 10;
            case 'L': return 50;
            case 'C': return 100;
            case 'D': return 500;
            case 'M': return 1000;

            default:return 0;
        }

    }
}
